I just started flyin my Sig Mayhem. OS 120, CG 5.5" and 16-4 prop. Tonite I noticed everytime I try to hover it yaws to the left. Do I need to add right thrust to the engine mount or is this a lateral balance issue? I also noticed that whenever I roll inverted it wants to pitch down is this a CG issue?

Thanks,
Tom

yes. move your CG back until upright and inverted needs no adjustment. lateral balance could be it, but some right thrust will help. probably about 2 deg

A Little Right thrust might help.. But think about the wind on this day? I've seen guys at the field complain about thrust angles when they were trying to hover in a crosswind! But mostly move your CG back a hair and think about that the wind is doing.. Then if it still yaws to the left... Add about 2 deg. of right thrust

Yea, I was paying attention to the wind. It normally blows here(Nebraska) but that day was unusually dead calm.

Well then I'd say try to move your CG back a tad more... Then the tail will want to stay under the nose. (think of a pendulum) But not to much as it may become unflyable... Otherwise add a couple degrees of right thrust and see how it does